Wood-grinding means



June 9, 1925.

G. NENZEL wooD GRINDING MEANS Filed Aug. 25, 19,24

Patented June 9, 1925.

' UNITED STATES TPATENTI OFFICE.

GEORG IQYENZEL, OF HERISCHDORF, NEAR WAR'MBREINN, GERMANY.

WOOD-GRINDING eans.

Application filed August 25, 1924. Serial No 754,036.

To all whom it may concerns Be it known that I, Gnono NENZEL, a citizenof the Republic of Germany, residing at Herischdorf, near lVarmbrunn, in

Silesia, Germany, have invented new and useful Improvements in\Vood-Grinding Means, of which the following is a specification.

This invention has reference to means for the manufacture of groundwood- It is in tended to facilitate the process: of manufacture, toincrease the output and improve the quality of the product. In Viewthereof it is one of the important objects of the invention to feed thewood under a uniform pressure by mechanical means to the grinding stoneor similar grinder without the use of a follower by which it is.customary hitherto to push the wood towards the grinder.

In accordance with this invention the feed ing is effected by screw-likeor substantially helical means which are adapted to gradually take holdof the wood with increasing force, and during such action and bypositive means crowd the wood under pressureand uninterruptedly againstthe grinder. These feeding and retaining means are mounted in recessesof the containers for the reception of the column of Wood. By therotation of these feeding means portions of the screw threads are forcedinto the logs of the heap of wood, so that the heap in consequence ofits engagement with the helical or screw-like bodies is positively feddownwards by the same. In order to gradually press the thread groovesinto the wood without, however, necessitating an excessive-- ly largeexpenditure of power, the screw-like or helical feeding bodies or thelike are either inclined in such a mannerthat their axes of rotation attheir lower extremities will intersect under a very acute angle; or,with the parallel mounting of the screw-like bodies, they areconstructed in such a manner that their diameters are increased in thedirection of the grinder, with the effect that with increasing force ofpressure the screw threads are cut into the heap of wood at anincreasing depth. By this means a reliable feeding of the wood isproduced, and at the same time the logs of wood engaged by thescrew-like bodies are forced away from the walls of the containercharged with the wood in the well known manner, and in view thereof thefriction of the wood against the walls of the container is diminished. I

j The invention will be more fully described with reference to theaccompanying drawing in which Fig. 1 represents that form of theinvention in which inclined screws are used to push the wood towards thegrinder. Fig. 2 represents that form of the invention in which the woodis pushed towards the grinder by helical bodies, the diameter of whichis increased in the direction of the grinder.

Referring to Fig. 1, above the grinding stone or the like 1 the woodcontainer 2 is disposed. In two oppositely arranged side walls of saidcontainer 2 a pair or a pluralit-y of shaft-s or spindles 3, providedwith sharp screw threads are mounted in such a manner that the threadsin the vicinity of the grinding stone 1 project into the container 2,while further away therefrom in the upper portion the threads recede,approaching the walls of the container more and more. The spindles 3 maybe positively operated from the grinder shaft 4. It will be evidentthat, after the charging of the wood container 2 at a correspondingrotation of the spindles 3 the screw threads of the same will becomeengaged with gradu ally increasing incisions into the wood to be ground,so that they produce a uniform feeding of the wood and crowd it againstthe grinding stone 1 with substantially unchanging pressure. In view ofthe inclined position of the spindles 3 the screw threads during thedescent of the column of wood become more and more deeply impressed andengaged with the wood, so that the wood,

even if it comprises logs of different size, is grasped with increasingfirmness, and is thereby prevented from yielding to the pressure force.The pieces of wood seized by the spindles are at the same time crowdedaway more and more from the container walls, resulting in a more compactand denser arrangement of the wood, so that the portions of wood whichare relatively centrally disposed in the heap, areforced with equalpressure against the grinder likewise. The modification shown in Fig. 2differs from the before-mentioned construction only by the arrangementof screw-like bodies 5 the diameter of which is increased in thedirection of the grinder. The action of these bodies is the sameas abovedescribed. It is immaterial with both modifications of con.

struction Whether the column of Wood is forced against the stone fromabove or "from the sides. It is also possible to crowd several columnsof Wood against the grinder under different angles. The crowding bymeans of the novel device according to this invention may also beeffected against the front surface of the gril'iding' stone or the like.

I claim 1. In a Wood-grinding apparatus the combination with a rotatinggrinder of a Wood container and a pair of stationary rotatingfeedingscrews partially projecting into the container at its front and backWalls, said screws being inclined in opposite directions to grasp thecolumn of Wood during its movement toward the grinder, by the screwthreads with gradually increasing incisions.

2. In a Wood-grinding apparatus the combination with a rotating grinderof a Wood container and a pair of stationary rotating feedingscrei'v-lilze bodies partialiy project ing into the container at itsfront and back Wall, said screiv-like bodies being constructed With a.diameter increasing in the direc tion of. the grinder.

In testimony whereof I have signed my name to this specification.

GEORG NENZ EL.

Witnesses F. NEROLF, C. LANGE.

